Vegetable Oil SVO WVO waste cooking oil as biofuel

[David]

Frybrid style filtration advantages:
1. simple.
2. Low energy needs
3. Lower cost may be achievable
4. Acceptable filtration and de watering can be achieved.
Disadvatages:
1. Must replace filters
2. Requires a longer settling time

While I have not tested the still design specifically, I have processed enough oil to know that the heat and settle method for drying to fuel ( HPT) standard is basically flawed.

If the oil put in is extremely good to start with and very low in water content, you may get away with it. For the oil I have seen that myself and others collect that I would call normal or average, it will not get oil to passing the HPT.

Given that sun has now developed measuring practices and methods that show the HPT is not accurate anyway, your going to end up with oil that is basicaly unsuitable for fuel use and be open to problems that come from that.

I'm actually surprised people supposedly " In the know" would support a system like the still method. Maybe those using it get really exceptional oil or test to a lower standard than myself and others do but basically it's a flawed method.
I don't use a CF myself either but I have palyed with one and seen the results and to compare something as crude as this still method to the output from a CF really is laughable.

Settling over an extended period is very effective in removing free water and solid contaminants. Any system that trys to settle the oil over a few days will have very limited effect. It may remove the course debris and free water but it will leave a lot of undesirable elements behind.

I use extended settling but it is still not enough to remove free water so I have a specific method to do that. Any oil processing method that does not physically address and actively remove the water has a very low chance of success IMHO.

I saw some research a while back which I can't now find that said dewatering oil was impossible if it contained dissolved water by settling which was exactly the conclusion I had come to myself.

If a contaminant is attached and bonded to an element and it is all dispersed within a vessel, where is the difference in weight for the gravity to act on to pull it out? Perhaps it is sufficent to work over extended periods of time but I can tell you a year is not extended enough.

The heat and settle or still methods would pull out free water and may allow the oil to pass a crackle test but it would not work on dissolved water or any test that determines the oil to be dry to that standard which is what I want to achieve.

[compostbrain]

David,

So what's your method?

[David]

I settle all my oil for 6-9 months.
It is then pumped into a drum where it is recirculated and aerated at the same time it passes through a 1-5micron water filter. There is a fan on the top of the drum sucking out moist air.

In optimum ( warm , dry) conditions I can process 200L of oil to pass a HPT in under 30 min. In less than Ideal conditions ( cold, raining) it may take 2 hours or more.

The pump I use is 300W and if I have to add any heat, I do it courtesy of my waste oil burner.

[harrisonm3]

I used an OC-20 for a while and then found a good deal on a pump / motor combo on a pump that pushed 3 times for fuel. After searching around on the internet I went with a larger centrifuge from PA Biodiesel. Model number k150 showed up without any of the accessories i.e. t's, barbs, and gauges. I called them and they paid me via paypal for my cost of those parts at my local hardware store. Both units are similar in craftsmanship. PA's system works fine for me.